This invention relates broadly to wind operated musical instruments and particularly to those musical instruments which are resonant in response to vibrating air columns induced therein to produce tones of various different pitches.
Conventional wind instruments may be categorized in accordance with the manner in which a vibrating air column is induced in them. Thus, there are lip reed instruments, examples of which include trumpets, coronets, trombones, french horns, and bass horns; reed instruments, examples of which include clarinets, saxophones, oboes, and bassoons; and split-air-stream instruments, examples of which include piccolos and flutes.
In each of the above-mentioned instruments, as well as in many other instruments, sound vibrations are created at an inlet or mouthpiece and these sound vibrations are channeled through an elongated instrument tube whose effective length is configured, that is lengthened or shortened, to create resonance therein so as to amplify the sound vibrations and promulgate them to the surrounding area. The original sound vibrations at the mouthpiece are created in different ways for different instruments. For the lip reed instruments, the vibrations are created by vibrating lips whereas for the reed instruments the vibrations are caused by single or double reeds. For the split-air-stream instruments, air is caused to vibrate by passing over air-splitting baffle edges. In each of these instruments, a musician can control these initial vibrations with mouth activity by controlling the quantity, velocity and/or direction of air flow, by the position of the lips, etc. By using mouth control, a musician can control to a great extent musical sounds which exit from a musical wind instrument, and in this regard, some instruments, such as a bugle, are played totally by mouth control. However, mouth control related to a single effective air column length is somewhat limited and does not allow a full range of musical notes.
The frequencies of the vibrations at which an instrument is resonant depend upon the length of the instrument, that is, the length of the tube between its air inlet and its air outlet. This length determines, but is not quite equal to, the effective length of the air column in which the sound waves are formed that, at certain frequencies, cause the instrument to resonate and thereby amplify the sound output of the instrument. It is well known that, to resonate at any given frequency, an instrument must have an effective air column equal in length to an integer multiple of one-half of the wave length of that frequency. This forms the basis for the so-called "harmonic series" of notes that can be resonant and amplified by an instrument having an air column of a given effective length, which series may be expressed by the series of fractions 1/2, 2/2, 3/2, 4/2 . . . n/2, wherein the numerator represents the number of one-half waves formed in the air column.
The common bugle has a single fixed length and is therefore capable of resonating only at frequencies within a single harmonic series. It cannot be used to produce a complete major or minor scale. In order to extend the range of the several instruments mentioned above, so that they may be used to produce not only major and minor scales but also complete chromatic scales, the instruments are provided with mechanisms to change the tube and effective air column lengths. Such mechanisms usually comprise telescoping slides, openable ports, or depressible or rotatable valve keys to provide openings to differing combinations of tubing sections. Because of the ability to change the effective air column lengths, the instruments can be used to produce multiple sets of harmonic series and thereby to produce complete chromatic scales.
The frequency, and therefore the pitch, of vibration of a wind instrument depends upon the frequency of the input to the instrument. Typically, a wind instrument, including its mouthpiece, is so constructed that one may produce frequencies beginning with the first or second harmonic number and, depending upon the skill of the musician, extending upwardly through several harmonic numbers. One may change the inlet openings so that the frequencies produced tend to be in the higher harmonic ranges. For example, an instrument made by equipping a bass horn with a conventional trumpet mouthpiece may not be usable to play the lower harmonics but could be used for playing higher harmonics than can be obtained using a conventional bass horn mouthpiece. This is because the bass horn mouthpiece is designed to enable one to vibrate the lips at lower frequencies than possible with a trumpet mouthpiece, at the expense of higher frequencies available using a trumpet mouthpiece.
As those skilled in the art are aware, the number of scale notes between the members of a harmonic series decreases as the harmonic number increases. This phenomena is demonstrated by the following Table I, which is for a trombone having an effective air column length of 9.43 feet. (This Table I and Table II and Table III below are calculated using an assumed speed of sound of 1100 feet per second--which is not quite accurate but is sufficient for purposes of understanding this invention.)
TABLE I ______________________________________ Wave Harmonic Pitch Length Scale Air Col. Frequen. ______________________________________ 2/2 A# 9.43' 116.54 cps 9.43' 116.54 B 123.41 c 130.81 C# 137.59 D 146.83 D# 155.56 E 164.81 3/2 F 6.29 174.61 9.43 174.81 F# 185.00 G 196.00 G# 207.65 A 220.00 4/2 A# 4.72 233.08 9.43 233.08 B 246.94 C 261.63 C# 277.18 5/2 D 3.78 293.66 9.43 291.35 D# 311.13 E 329.63 6/2 F 3.15 349.23 9.43 349.62 etc. ______________________________________
One may observe from Table I that a trombone with an effective air column of 9.43 feet is capable of playing notes of ascending pitch in the sequence A#, F, A#, D, and F. Of course, a trombone usually has a slide for increasing the length of its effective air column so that other harmonic series can be formed. One may also observe from Table I that there are six half-tone notes between harmonic 2/2 and 3/2, four half-tone notes between harmonic 3/2 and 4/2, three half-tone notes between harmonic 4/2 and 5/2, and only two half-tone notes between 5/2 and 6/2. If the harmonic number is raised high enough, an instrument will play adjacent half tone notes. (At even higher harmonics, an instrument would play quarter tones.)
A problem with musical wind instruments capable of playing complete scales is that they require considerable skill, patience, and practice to play. Not only must musicians be dexterous with their fingers to reconfigure the instrument tubes, they must also memorize all of the proper positions and coordinate them with their lip movements.
An object of this invention to provide a musical wind instrument which may be used to play more notes than possible with a conventional instrument having a fixed tube length but which is simpler to play than conventional wind intruments having mechanisms for changing their tube lengths. More particularly, it is an object of this invention to provide a musical wind instrument which may be used to play a complete major scale without coordinated mouth and finger operations.
Another object of this invention is to provide a musical wind instrument which may be used to produce a complete chromatic scale with a minimum of coordinated mouth and finger operations.
Another object of this invention is to provide such a musical wind instrument which has a reasonably acceptable tone quality.
Broadly speaking, the objects of this invention are the same as objects of the invention described in my U.S. Pat. No. 4,885,971, granted Dec. 12, 1989, and, in addition, to achieve results superior to the results obtainable with apparatus constructed in accordance with the teachings of that patent. U.S. Pat. No. 4,885,971 discloses a musical wind instrument comprising a single mouthpiece, an energy divider extending from the mouthpiece that divides the sound energy entering the mouthpiece into two or three streams, a tubing assembly for each of the streams connected to outlets from the energy divider, the tubing assemblies having open distal or free ends, one or all of which may terminate in a bell. A tubing assembly could also terminate in a straight, open-ended tube instead of a bell. The different tubing assemblies are of respectively different lengths so that they resonate at different frequencies and thus may be used to produce more musical notes than possible with a single, fixed-length instrument. In effect, an instrument in accordance with the '971 patent may comprise two horns with a single inlet, with the length of one horn having a fundamental (harmonic 2/2) which is one half tone above the fundamental of the other horn. Other workable embodiments may have two horns having a difference in their respective fundamentals of two half tones. Still other embodiments may include a third horn having an inlet opening common with the other two horns, the third horn having a fundamental which is higher, again by one or two half tones, than the higher of the other two horns. The tubing assemblies may have ports which are used to produce scale tones that are otherwise not obtainable with the unported tubing. Major key scales can be played on such a horn without requiring hand control. Full chromatic scales of consecutive tones can be obtained with the use of ports.
Although instruments made in accordance with the teachings of the '971 patent are usable, there are disadvantages in that the lip buzz energy input that is traveling through the non-resonating branch or branches ends as an air rush sound so that one-half or less of the input is used to cause resonance in the resonating tube assembly. Also, musically inferior tones are occasionally caused by an averaging of pitches produced at the same time in more than one branch. A further object of the instant invention is to avoid or minimize the drawbacks of the '971 instruments.
In accordance with this invention, a musical instrument comprises a single mouthpiece, a hollow, outer tubing assembly or horn connected to the mouthpiece and terminating in a bell, and a hollow inner tubing assembly or horn mounted concentrically within the outer tubing assembly at its belled end. The inner horn has an open, upstream end located inside the outer horn and either an open or a closed downstream end projecting outwardly from the belled end of the outer horn. If open, the downstream end of the inner horn could be belled or tubular. In the presently preferred embodiment, the inner horn is in the form of a straight tube which is closed at its outer end by a cap.
Tests have shown that the presence of the inner horn can produce two beneficial results: additional scale tones can be produced without the use of valves or slides and the frequency of certain off key tones produced by the outer horn alone can be corrected to be "on key". The correction of the pitch can result from an averaging of tones produced by the combined horns and from the lowering of a pitch produced by the outer horn because the air column of the outer horn is partly obstructed by the inner horn.
In a preferred practice of this invention, a mouthpiece is used which enables the two horns to be played without substantial difficulty in a range of frequencies beginning at the 4/2 harmonic and extending through the 16/2 harmonic. A musician with a well-trained lip may extend the range through the 20/2 harmonic. Such an instrument with an outer horn and one inner horn can play a complete major scale and several additional scale tones.
Further in accordance with embodiments of this invention, the outer horn may be provided with one or two normally closed (by keys or the musician's fingers) ports adjacent its distal or free end, namely an "accidental" port for sharps and flats, and a "scale" or range-extending port, both ports being near the belled end thereof. The port or ports, if used, are spaced to provide a musical interval of half tones of higher pitch with respect to the originating horn pitch. They may be made adjustable to permit slight changes in tuning to accommodate other instruments of fixed pitch when playing in concert.
The inner horn may have a telescoping slide for adjusting its length to adjust the family of pitches that it causes to depress. The inner horn may also be adjustable to different lengths relative to the distal end of the outer horn to adjust the pitch of the instrument.
In another aspect of this invention an attachment may be provided that adds an inner horn to an existing horn to convert the existing horn to an instrument capable of playing a major scale without the use of valves or slides.
Other objects and advantages will become apparent from the following description and the drawings.